Ahead of Donald Trump’s speech on illegal immigration Wednesday in Arizona, his campaign is reiterating that there will indeed be a physical wall along the U.S.-Mexico border as part of the plan.

“There’s going to be a physical wall, and there will be a physical wall on the Mexico border, and as we know, Mexico’s going to pay for it,” Trump campaign senior communications advisor Jason Miller said Tuesday on “Fox and Friends.”

A day earlier on the program, former New York City Mayor Rudolph Giuliani, a Trump supporter, had said Mr. Trump would build “a technological as well as a physical wall.”

Mr. Miller said “nothing has changed” in Mr. Trump’s stance on the issue.

“He’s been remarkably consistent,” he said. “He is going to stop illegal immigration. He’s the one candidate” to do it.

“We already deport a lot of people every year, but what we have to do is do a much better job than what President Obama has been doing,” Mr. Miller said.

“Mr. Trump has said that we’re going to start with criminal illegals. We have to go after the really bad ones and get [them] out of here first. That’s the number one priority,” he said.

Mr. Trump suggested last week there could be a “softening” in how to deal with otherwise law-abiding illegal immigrants with longstanding ties to the United States. Later in the week, he clarified that people would have to leave the country and come back before being granted any sort of legalized status.